Turntable drive



C. P. WOOD TURNTABLE DRIVE Oct. 4, 1932.

Filed Dec. 28, 1929- 2 Sheets-Sheet l I NVENTOR [flare/a2 1? Wand BY WATTORNEY C. Pa WOOD TURNTABLE DRIVE Oct. 4, 1932.

2 Sheets-Sheet 2 INVENTOR Clzmmce 1? Wm BY w 424 ATTORNEY Filed Dec. 281929 Patented Oct. 4, 1932 UNITED STATES PATENT OFFICE CLARENCE P. WOOD,OF NEW YORK, N. Y., ASSIGNOR, BY MESNE ASSIGNMENTS, TO ROBERT B.KILL-GORE, 0F SHORT HILLS, NEW JERSEY TURNTABLE DRIVE Application filed.December 28, 1929. Serial No. 417,075.

irregularity in the feed of the projector wastransmitted to thephonograph and caused the turntable to almost imperceptibly accelerateor retard resulting in a wavering reproduction of the sound groove inthe record.

It is my object to overcome this defect in direct coupled machines bymeans of the phonograph hereinafter described, as well as to provide asimple, cheap and sturdy phonograph which can be quickly and easilyconnected to any projector head and which does not interfere with thedoor in the projector through which access is had to the mechanisminside the head for oiling and cleaning purposes. 7

In the drawings Fig. 1 is a cross-sectional view of my improvedphonograph; Fig. 2 a view of the structure of Fig. 1 on the line 22thereof; and Fig. 3 a detail view of the mechanical filter on theturntable shaft.

My phonograph comprises a base 1, carrying a vertically adjustablehousing 2, held at any required heighth by a set screw 3. This housingcarries a divided turntable shaft 4:4: whose meeting ends are preferablyrounded as shown in Fig. 1. The upper section 4 terminates in the recordcentering pin 5. The lower section 4 of the shaft rests in the bearing 6and against the thrust bearing 7. The upper section 4 of the shaft restsin the bearing 8 and is provided with a thrust bearing 9.

The two sections of the shaft are coupled together by a resilient,elastic mechanical filter comprising a yoke 10 on the shaft section 4!and a like yoke 11 on the shaft section 4, with an elastic rubber disk12 secured to the yoke ends, which are in staggered relation as shown inFig. 3.

sleeve 23 apart.

The turntable 13 is very heavy, about 120 pounds in practice, so thatthe inertia while revolving will resist the effects of any slightvariations inthe speed of the driving mechanism and hold the turntableto an absolutely steady speed.

The turntable and its'shaft are revolved by means of a worm and gear. Agear 14 is mounted on the shaft sect-ion 4 below the mechanical filterand a worm 15 is cut on the shaft 16 which is carried in the bearings 17and 18 and projects through the bearing 18, the extended end carrying apin 19, the bearing 17 receiving the drive thrust.

, The coupling shaft connecting the phonograph to the projecting head ismade in sections. The first section is in the form of a sleeve 20 havinga notch 21 in its end adapted to engage the pin 19 and carries a disk 22on its other end. The second section is in the form'of a sleeve 23provided with slots 2431K]. carries a disk 25. The disks 22 and 25 arecoupled by means of a flexible rubber disk 26 to form a cushioneduniversal joint. The third section is in the form of a shaft 27 whichslides in the sleeve 23 and carries a pin 28 engaging the slot 2 1, thefree end .carrying a disk 29. "A spring 30 wound around the shaft 27forcesthe shaft 27 and The fourth section comprises a shaft 30 with apin 31 atone end and a disk 32 at the other. A. flexible rubber disk 33connects the two disks 29 and 32 to form a cushioned universal joint. Anotched nut or coupling piece 34 is adapted to be secured to the exposedend of the main or crank shaft of the projecting head and engages thepin 31.

I An arm 35 may be mounted on the housing 2 to carry the reproducing. orpick-up head of the phonograph.

In operation the phonograph and projecting head are coupled up tooperate as a unit, being driven by the motor of the projecting machine.The record and film each has the starting point marked thereon and afterthe appropriate adjustments are made the motor is started and theprojecting machine feeds the film and drives the phonograph insynchronism therewith.

The unavoidable slight irregularities in the speed of the projectinghead are absorbed in the flexible rubber disks 12, 26 and 33 before theycan overcome the inertia of the very heavy turntable 13 so that anyslight variations in the speed of the projecting head 2 will cause therubber disks to deform-slightly to filter or absorb the irregularitieswithout affecting the constant speed of theturntable.

Should the projecting head he suddenly I stopped the gear 14: will climbthe-worm 15 slightly lifting the mass of the turntable and then theweight of the turntable will cause it to slowly settle back, coming to ashockless stop. V

Whenthe door of the projecting machine has to be opened to oil theinterior mechanism the shaft 2? is slid further into the sleeve 28 bycompressing the spring 30 and the pins 31 and 19 cleared from the slotsso that the projecting head is in the samecon'dition that it would bewere there no phonograph associated therewith.

The principle involved may be summed up as the utilization of the massof a very heavy turntable to store up inertia to prevent speedvariations and the interposition of mechanical filters between theturntable and the projecting machine to absorb any irregularities in thedrive. a

I claim A phonograph comprising housing, a divlded turntable shaftthere1n,aheavy turn- I table on the upper section of said, shaft, a

yokeion the lower end of the upper shaft section, a second yoke on theupper end f i the lower shaft section, an elastic connection engagingboth of said yokes, aworm gear on the lower shaft section, a driving ormen- 7 gaging said worm and adapted to be connected to the main shaft ofa moving picv ture projector, whereby on the sudden stoppage of saidturntable the rotary movement thereof is converted into a verticalmovement for stopping said turntable without shock ,orjarh y Intestimony whereof I have hereunto subscribed my name.

CLARENCE P. woon.

